SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '370f6a1e7b92fa965021194df59e2e508e47c5cde85ae3eda520a6bddf27dfde' 
  AND token = 'LR4AFL/XHPlQuZNWx10wIMLQqZa8SDZC1msimJbtDVY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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