SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b0d5ad95bcbe74792a41569ed2267fbbb88c2d8b7db9a5ff63dcef73a68bb78' 
  AND token = 'vimNF7fZWiMHJcAAIDLizttrCu6naj91qhaLJr07Ssw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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