SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4965009e9d57bbdc58450d36eebf8a1f4faa4eace8e176001a610cb8f77d6bcc' 
  AND token = '7nhnqx927VcBtrTqN+Tu9bGYkSe30kZrggnoZhUnZpg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}