SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6473fecba7901e0acdbc6a279af61ecbffb0941b7941e2715ec23dc853208a24' 
  AND token = 'Y4KBsIaCr60OBRBrBxq6XOvQcgShlWyZh98b7T8FPP4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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