SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd3da27684b21c5e2bfb7e386a875ebf4ce3eb755dec0c74125c684e780137a94' 
  AND token = 'xEdwY3pKXxYyXwqbbC3bJ71T/N4pxmTQK3mqpVB7Bo0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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