SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '94e1a8f89809560c3e9106889697125cde419e88344cd5814bd52e397347dce2' 
  AND token = 'gliqKnwh2dyXISM92znOA5VbYjFhKK3w/pSt+Fg+mes=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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