SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2064cc7bd675511cb84660f8fc9d99ed39ad9a76228adcdd8fca4c3948892bdc' 
  AND token = 'LanPpZqw81gpKSotQw+I0mk/QlWbTpXYvLJVguh0mC8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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