SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'efbaa03486d819344905efec7aaafe9a824fb5ccd92a458f75b4cbe0febc2214' 
  AND token = 'whB7jviq55XZf+cj9uhQRolGJUIuZ2oNzjJDxzNsPaU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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