SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4056b3be654dc4f9d7b148a24dc9967e176aa42006f814dd7a210b5032ee828d' 
  AND token = 'RySmW1Yu0gVejQUPv97DqQ5/oMTIeDclopWdkDqr1/s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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