SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7d163e82258934f026a82eee8c71386322ec5132568c088b5618c8f222a2f365' 
  AND token = 'mlAOT3+Yiu+QT2bjLMqn9bcnqWZr0jwccIKw3b9Qxhk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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