SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc109e2e0c90af4ef7c697748fb644d62be181c1e9cf3cb4f64604c2a032c575' 
  AND token = 'lFd78dA8Ldu1dSOcqoWoyOhkUuP/CYOLuKvg0+1RPqI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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