SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e0c037cf5c20d26f308d63de849f141f64e03980c19722ebef554d19b9c4c27d' 
  AND token = 'C+U3KGGWMkCQISbcdXaqIM8o9ImGoEgEseES96R9wJ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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