SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62a97dfe7f23095218892fa2b1cb99dfb41bf5c303a634b654aa2adbb7b40cf7' 
  AND token = 'ZhHgdDrBJu7J+R0M1Ik+7PZPtoEVUkplZciVFAtCaOE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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