SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '596a457592bbe5d2f0958caba9adc4119d98272d7c2b5d063117cd68baf196b1' 
  AND token = 'ciWpsKwSORNiz2t5kMITQs5+gTFDV6yePM9CowUhLrA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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