SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f496b92084c4244f6152b364dab7d6b5824866d1b11f626a3bfee2b3c36671bc' 
  AND token = 'ZpBWeWFjaGv7/XRVKvf8qfeSvhrwJvSHchBWbM5z7GA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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