SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70806edecfea343eb8e42f3be71515810eb9f6e7cf6c44fed802fc6b89720278' 
  AND token = 'wozGLzgpjWvAids1bq+m/GogcEFewzN3Wzcu44C52Yw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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