SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '636a0358e1aeb89f0f4645ca3908bdc39fc5e48389cc693f47399436a1d7c9f6' 
  AND token = '06J4+H6OlWBOThknkd/tSLp8i3rLUcj1bwEOZvpky2w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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