SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48414c683488184d0dd09415542f0a79a871346f5d8877499040a621ad2128d0' 
  AND token = 'hCk1HeF9dxmWegGTl67fYXy7i2JrN/uwsK/Z/lx4tbc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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