SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b18356112f753b528a7173912e25e39999c9221716c150f149eaf8624c2bd06b' 
  AND token = 'vGHKjb6dyV3PvlSTI7ie3pvDpvfHBvfMK0tSyt6oQ/M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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