SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bff628f33138866305826f652b96b11afac2864bfdbf542fb9b9cd0ae23b5aab' 
  AND token = 'hzGpcvi3Dz8rbGaF3afKoZ3W1MvVQtnfcATUNOn0v9c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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