SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bfac51fd6dcd5e7a25879f5170948b447291ef4df0f33f8b3f0f38fbd430e21e' 
  AND token = 'UmPtxDO2rFtHA+DPLWzb0zgUdjpJwmgsvrzHUGaDRhU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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