SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4fd01760d9405567a0e6c5b06c6428b226bb5bb2a2bd0655d91b081252a9fb7b' 
  AND token = 'B3uXQ8BwVU4GfFV/getAHAEK9G6W1Dc/Lq0ucIoaLF0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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