SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e47c545e559cc3884c109b7d826be25ff39366493dd7b3fb3b58af56accfd866' 
  AND token = 'yDQ22cgvdyM/TTSZd8RNca9JIiLDtV0XQWMPkxA7/n8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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