SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58707af1d2fa0169c112635b3579a07c2c89ad5dc896a53523f01ca3eb8490ba' 
  AND token = '2FPdK6FhYGMoOEt9OAteYUFYOiaZYJhmAjTS8qs7SsQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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