SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63681f50ddb50394bd160f979e35e2955bda58cb458b47f5b4b9257b58fb0b55' 
  AND token = 'IBcEmAJ/ZD6WxOtg9jhddmtuo+yRUsWTSnI3RHycIS0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}