SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f64114c04ed6c5101a86fcb5357420444d15a5692f7e80b9f3193b3d29e789b' 
  AND token = '7jID85NVWOXCniGBsEWjYNCFH0faElGhKrB+nTG6X4s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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