SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3cd18373e06a075f221af66ff29ed9b3df7d45b9c24e39e43cf6241d92d28be1' 
  AND token = 'nFAuWgq/BDyDvX2clYMFktioNvKKZtADM6Yh+LZ4I4A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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