SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6e24b09383f9d3297b62503a1511b225c4a1445d080672b646ce0d50775f4548' 
  AND token = 'yYcYfel8rX26SVaPFK3jHi9TRnPXs5XN4Aphk4QJRLo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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