SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62df642202b3d1b9b6cef88ea2200dcb1c10f94124b6f2eefff082a05e6e3ae9' 
  AND token = 'PkPdf2SaKTdEOGI94Gr+qtB4YGLUQUi3DiSLo/OZSZY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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