SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '276bfb7082ccda97775c2b66712e604a8ac174323054ea9497cfc4a556f5dadf' 
  AND token = 'g+KGWf+rRqmIGwAYRXq+eFIK0Zt2wyz9tEDppxxYDLA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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