SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd86644688d105263acad6a4d0a8c7b202a3426cbcc55942bbfae1f99bbab26a2' 
  AND token = 'q+8HrL4cggwkLGlfNvlL2T+hCmfr8BgirunZdtrzFMk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00061

JSON explain

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