SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9a07d127efbdf7874e214e834e02e25eea668454052f2d058d16a497363b10cf' 
  AND token = 'oW1uxbo0wHhJiKyjfhHWg/YnK1pszQ9DM7kkGXqVrwc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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