SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5236b4f5761d413f4220748527290a31ecfd6cbbc8b50892bd5ab4218b5c3832' 
  AND token = 'Dw5OKgo544sqJdAx2imA4mTTE3hkXZs+ZTrjndM4mWc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}