SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c0f47fe331574fd5c712bd4973dc839fac054dcf92ee2ebe4c12defad2835731' 
  AND token = 'eBj2+oUKkLYvtNsfBpjSnn1W50cVGhRKrQQbTL6rWQw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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