SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1ad4ea74d608c1427aaa32778923677c01aa8a222beecd6ed75d4ed81a6a84f1' 
  AND token = 'UBf31mu57nbt59LI4nZBx1m/ZnZ4fV/nh4JxHcJH7Eo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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