SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '038a52f29b2a4381bb346240c1a1125680287d8df1536c9ba88b4a86744efe3b' 
  AND token = 'lvdfJs6BdYoThTJBt2vSVj8Ut6a9gJVimoWRb1TAnZI=' 
  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"
    }
  }
}