SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1aaca90d2697d088607f41e6237e68c3ffea0db0717ff5e6d0da0f181c45f91b' 
  AND token = 'YyHaCUR1Rsl3BVWi2k2w4WOcY+uAPY4gY8uyjtniS0U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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