SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3b4990fc5a7a8077f526f51f5c67d2e1ed5d8119d46c7e574a66110f502a60aa' 
  AND token = '0mzYYYh5JOaThQ2nsXFsPEa3hdrTj2p9BvpKvX64HLc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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