SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '190f21adef9a495ac0b6142e31912e1fbaaf8cb7b93f55795151345e7fc338df' 
  AND token = 'l+sb2KiKrqoPCbrVqyt+SbpfsFeSHDvbnqlvWdjOH1k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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