SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4a3083a8c804965ef56989dc74293b381f2155ac5e648cf5794c1712041e6da1' 
  AND token = '0H03/KQCa8jOxNMVLSDT6wXqLBjIzJuc+dF5hq+5DVg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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