SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cda315a186896113be8aecea46e8ef34c8e3433dc656a7b4c56d708520fda596' 
  AND token = 'Wl6KV1XFd4el8OIrsVbstZsdCmLslkRHAVk9g5IQ04s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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