SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f03dad0cdcdf715e828c5901d88298295fde4fcdbdf19fa35a1366861bf98518' 
  AND token = 'Q76vnXGHVtmCO6RYNKYHfx4WZ+dDAq8LOshJADh8r3c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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