SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f55dc9d87fadbb96754c4fa6b1904eb40c93202d2ab9c4823b41ffb6956c8402' 
  AND token = 'lI6WhP3cDcWfuf+zbT69+vhkTkwcr77A2uA7EtqoYWk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00011

JSON explain

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