SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b48a3f297ed92c74a3b9f725eabec4a326cfd61aeec6362c6661e8f9fab63ead' 
  AND token = 'aqJyaJ5mowHDyMykMk6iixTovqHDp4mktnbCL6kKFOo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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