SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b988ad6690102c4966785f450f24c3a40e42c5a783243c66515efb69d5617674' 
  AND token = 'IvAK/aAOMCcObK1mUlW5Kuo8oHB4k/aqkLUq/lAUt5c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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