SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ff8fdcb7fd4597f84cfa65ddb1df2d98826f7173de2298dd4737bf4a2ea9dd31' 
  AND token = 'r+VeYcmjRc0KZu8JNMgTs6GBYErKR+Dyt8H0yNJWhk0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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