SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '838c5f971bf5a08a3d80e8a09852b2280554f745727932320e619304e66bc0fd' 
  AND token = 'NdRQewsATtTQnoJHXe6cmQTOsX9zBBGTevNSFXoxJqw=' 
  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"
    }
  }
}