SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7180ce00a2eb4cc3d454ef869bec70bba74dcfbc59b282eabb87c84740f92453' 
  AND token = 'CBE3wP2CueHiaMVo6aWS+wPffwdVCg9pTmZOmuy55X4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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