SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c9165bd6b9b54f419a65a3411aba3c3215ab5ab04586b4d8b6f53f770e8d91ab' 
  AND token = 'rlY+BuXikjTaIQl1uqknM/vAuhBPvhaiT2VpGNxce7w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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