SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '895ef7bca99aebe685bd10df967230e3aedecc5fb1711671d452b3f87b1648fa' 
  AND token = 'tzalB0FSbdu/AiMKuifEQ3kZBXuRy+XxxSmoh3MpNjc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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