SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45faf1878debaba76286077b5483b70343406b5961be5a3a649d5a70974803f8' 
  AND token = 'rhNuR/vqtYZa2PhQ199r0VdSt2zUEHMZqJQl1OvlL9c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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