SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8ccfac9f002fcfaee11859841b5ecad3254dbafbb1aebfe7c570ac2c197dbf80' 
  AND token = 'eWgND4FXFickOByo8GRnvC0xB5MK9cbln2g9SpDQpsc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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