SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c57e4a10966b27e675d1c06ac63d784a707fff0a383b38aa3258f55ba1d2ac04' 
  AND token = 'YoCw0++KynJuAPgRHknDUhgoq3hVp1/OY5NjQTqDPJg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}