SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9295c01cd91506d72a5092def0adfa0355c3aa0b1698de55846cba6a5338bcec' 
  AND token = 'Q1rwv43H4kZq3N4VDhgaMSDXREoKO6KoQ0zW8cEJE+4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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