SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6b035e9a11aaa995322a6d9755b024018a4e4019abf0a76a1e2bc07e188c9105' 
  AND token = 'RhVXtGA0UxfxghPMuoRnLvNEdMVkxf42YZN8L9lEuA8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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