SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd5dabd1d01584917ff516ca37aacfe164e039038649c49561e619ffa999b478c' 
  AND token = 'B+9ijrn2XeSQqw1OZ14PRy+M1JGIX5DLCUjH/c4b7hs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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