SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a2c5c398e90f70e8217a4d51d127caac03c725276bd4e164c8649da47718b043' 
  AND token = 'w7K4Jc4DtFzqBZh20sRBwP3MGNIGO3DgAYbYk9+S2Vo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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