SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ea00eedf50abfbfd974faf87391664b8d1800b28602c6c21cd6bd2565759b41' 
  AND token = 'QZAwPV8KbXtbzYrPcw/N1uRfwPt+Nsa2rzGh2SJhATA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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