SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'edb634de6581693f40214cf04d9dc67f71b1bdb48d342fdd1ed878a45f989946' 
  AND token = 'XEaDlVF+e2oBhqZL5Q265pBZFpIslCICOHDJweVE998=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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