SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64828d5eac5330125c85ec2bb43967788e4485a38d0af33d55c76f139c7bb7b6' 
  AND token = 'y89hlrdyKnZ0W4zzF2EqgIOwLtMC1kxoJ8WciBSP16E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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