SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2d0c0e2f2fa04a8c984e2bb6e6a97ecd9320b93167776f25db57c9286ea8f2d' 
  AND token = 'B1pOk/YIbT1xzbLBsqOxtxNCtOB75VtkHW0deipR9No=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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