SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '290358c697c1cfe4271f59e1cf9088ff98bc3652a3f4d7051605f757c0108539' 
  AND token = 'B5mSoIg5byJ9J/OWGtdS8wbxX+ahrGG5Z/phztPrvHs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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