SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '986a5b1081b5972ebc2dea1340aaf6d0f866bb66058508e9b41d183d38f4cd77' 
  AND token = 'bvcmmsgIrhC+p0YvXDIC1EjOMunYP8LYKWC2eApqX8k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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