SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9555b5247f551ea6075c7ab028013b86f387512377ad37fc9a17a834ea914087' 
  AND token = '8AJUPyFdVk/ZlPDp6yCgRoWspE4O8AxdsgtPPIDH3qo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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