SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea3446b6b79e2f99455986dcef6dcdf72f3dbebb9edc996c08aec7fdc1f22e11' 
  AND token = 'uadBJIrNJtKMCzho9UiW7jtNaedW+p3lQjL0Hq3gkwU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

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