SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af915e5f5e6671dcd0dfc19f91e30533ae25ccd93acca3d92bcd9a765f21f0e5' 
  AND token = 'zjytxRw2To/H0AdYngTrFSnWuGGx+U20h32CM0i0UUs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}