SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d005b5f18974d48ec96c6773aa4711f2089d6d2c8192c119eeb4b47a2c82312' 
  AND token = 'VvtGbJOHCbdIpUns90hqtd6SdsapjE+2gvgI16KNuZs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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