SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd645ee0cebb87605cef760e60208362e5c95ab43b87de00fa229b37e0585c6be' 
  AND token = 'bOwZpkbYLWDuTm7vWYERdrL2Py4tcIQyIrqxHCx+6mo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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