SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '02b75df9d3f1d14eecea480aad6b427cd5d43c4578847a9b428bceba91178391' 
  AND token = 'SJ+/lrzOnJnZvW3kfgKKAyFw3ADXV9lzJ4urkpgwwwA=' 
  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"
    }
  }
}