SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5320364e240bddbcb4062b20d86cf2e88f1b52facb1bfc23be83437d09c558b0' 
  AND token = 'jq4Ue3k7WINrP6Rpxm+AqwfX45tQSejT2UhHJ6OQ2sM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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